The present invention relates to a signaling apparatus. More particularly, the present invention is directed to an all-purpose, pneumatic powered signaling device adaptable for effectively transmitting signals above and below water.
It is well known that divers may use one or more tanks of compressed air to extend their time beneath the surface of the water. Such divers, often referred to as xe2x80x9cscubaxe2x80x9d (self-contained, underwater, breathing apparatus) divers, would benefit greatly if they were able to communicate with other divers below the water""s surface. It would also be desirable for scuba divers to be able to communicate with others when they return to the surface of the water. It would be ideal if one device could be used for both purposes.
U.S. Pat. No. 4,950,107 to Hancock et al., which patent is incorporated herein by reference in its entirety, discloses an audible alarm device for divers. More specifically, the audible alarm device consists of a pneumatically operated horn activated by a push button. The air source for the audible alarm device is a tap off the line from a scuba tank to a buoyancy compensator vest. While the audible alarm device is well suited for attracting the attention of others once the diver has surfaced, it is of little or no use while the diver is submerged.
Effective underwater signaling from one diver to another is normally performed with a percussion device of some description. For example, U.S. Pat. No. 5,400,736 to Gold discloses a hand-operated signaling device while U.S. Pat. No. 4,095,667 to Mahig et al. and U.S. Pat. No. 5,302,055 to Johnson disclose pneumatically operated pistons which impact on a diaphragm. It will be appreciated that in the later patents, the mechanical impact of the piston on the diaphragm permits the diaphragm to vibrate or reverberate, thus creating a pressure wave that can be heard/felt by other submerged divers.
Thus, pneumatic signaling devices, which work in either air or water, are known. Several attempts have been made to fabricate an all-purpose signaling device. For example, U.S. Pat. No. 4,998,499 to Nordbeck discloses a pneumatic signaling device designed to operate both above and below the water. More specifically, the ""499 patent employs a vibrating diaphragm inducing impulses in an attached air horn; the diaphragm and air horn can operate underwater by virtue of a lid, which lid can be detached from the signaling device when operating in air. In contrast, U.S. Pat. No. 4,852,510 to Joseph et al, which discloses a scuba whistle, which can be operated both above and below the surface of the water.
However, manufacturers have not been able to design a pneumatic signaling devices that works xe2x80x9cequallyxe2x80x9d well in air and water for a number of reasons. For example, air horns that operate above the water are generally inoperable beneath the water. For the sound generated by such air horns to carry any distance, it is necessary to employ a source of compressed air, which air source is conventionally carried as part of the horn assembly. Likewise, conventional whistles and bells are limited to signaling above water and are both cumbersome to carry and of limited range. Alternatively, it is known that when a piston impacts against a diaphragm, a percussion wave is created that will transmit above and below water. While a percussion wave may be felt some distance underwater, such devices are generally unsatisfactory for transmitting signals above water. Furthermore, there exists the need of providing a readily available source of compressed air capable of powering the piston. Moreover, even if the same source of compressed air can be employed to power air horn and piston signaling devices, the optimum mass flow rate of air needed to operate a pneumatic piston signaling device is substantially greater than that needed to operate an air horn signaling device.
It is clear that there exists a need in the art for an improved signaling device equally adaptable for effectively transmitting signals above and below water. Such a device should be as small as possible and, preferably, not require a separate compressed air power source that could add weight and inhibit movement of a diver. Preferably, the signaling device would be adaptable to employ a diver""s own source of compressed breathing air. As will become apparent, the present invention provides an all-purpose signaling device capable of utilizing a scuba diver""s air supply to power the device to transmit signals above and below the water.
There is a critical need in the art for an all-purpose signaling device that divers can utilize above as well as below the surface of the water.
The present invention is directed to an all-purpose, pneumatic powered signaling device that can readily be used to signal others above and below the water. The device employs a selector switch capable of directing a stream of compressed air to either a first component for signaling above water or to a second component for signaling under water. The all-purpose pneumatic signaling device is preferably integrated into the air flow passageway leading from a diver""s source of compressed breathing air, i.e., breathing tank, and the diver""s buoyancy compensator device for powering the buoyancy compensation system. When the selector switch is set for above water use and the signaling device is activated, compressed air from the diver""s tank at a first flow rate is directed into an air horn for generating an audible signal through the air. Alternatively, when the selector switch is set for below water use and the device is activated by the diver, compressed air at a second flow rate is directed into an enclosed cylinder and functions to drive a piston into repeated impact against a rigid diaphragm, causing the diaphragm to oscillate and transmit a percussion signal wave through the water which can be heard, i.e., felt, by other divers in the vicinity.
A significant advantage of the present invention resides in the ability to actuate the all-purpose signaling device by merely twisting or moving a selector knob to xe2x80x9csetxe2x80x9d the device in either the above or under water mode of operation. The signal can then be initiated by merely pressing an actuator button. The signaling device may be xe2x80x9csetxe2x80x9d for underwater transmission before the diver proceeds underwater or may be xe2x80x9csetxe2x80x9d immediately prior to use. When the diver returns to the surface, he may rotate the selector switch to xe2x80x9csetxe2x80x9d the device for air transmission.
Because the underwater component of the all-purpose signaling device includes only the single moving piston, there is little chance of the device malfunctioning regardless of the depth at which the device is employed. There is also no need for the diver to repeatedly depress the actuator button to continue to transmit a signal. A unique system of air flow passageways extending within the cylinder directs the flow of compressed air to sequentially propel the piston against the diaphragm or move the piston out of contact with the diaphragm before automatically initiating another cycle. As a result, one depression of the actuator button is sufficient to transmit periodic percussion waves that may be xe2x80x9cheardxe2x80x9d by other divers in the vicinity.
Advantageously, the present invention employs a quick-disconnect attachment assembly for joining the signaling device to a diver""s existing airflow system, which permits the signaling device to be easily connected and disconnected in the air line between the diver""s air tank and the diver""s buoyancy compensation system via a power inflator. This allows compressed air to continue to pass uninterrupted from the diver""s tank to the power inflator while, at the same time, permitting a small portion of the compressed air to be rerouted to selectively initiate either an above or below water signal.
According to one aspect, the present invention provides a pneumatic signaling device operable above and below the surface of the water from a source of compressed gas. Preferably, the pneumatic signaling device includes a continuous signaling device for generating a continuous signal detectable above the surface of the water operated at a first flowrate, a percussion signaling device for generating an intermittent signal detectable below the surface of the water operated at a second flowrate greater than the first flowrate, and a device for selecting an orifice sized to produce one of the first and second flowrates. If desired, the selecting device is disposed downstream of the percussion signaling device. In an exemplary case, the percussion signaling device includes a single moving element, which advantageously can be a bi-stable undamped piston.
According to another aspect, the present invention provides an all-purpose signaling device including a first signaling component operable at a first flowrate, a second signaling component operable at a second flowrate, a selector switch assembly for selectively creating one of first and second flow passageways sized to permit flow of compressed gas at the first and second flowrates, respectively, and an actuator which provides the compressed gas to the selector switch, wherein the first flowrate is less than that needed to operate the second signaling component. If desired, the first component can include a gas driven horn adaptable for transmitting audible sounds above water while the second component can include a device for creating a percussion wave signal that travels underwater. More specifically, the percussion device includes a cylinder having a longitudinal bore accepting a bi-stable piston and a diaphragm disposed across an open end of the longitudinal bore.
In the all-purpose signaling device discussed immediately above, the piston includes a driven end which impacts the diaphragm and a driving end opposite the driven end, the driving end of the piston is larger in diameter than the driven end of the piston, the cylinder includes an inlet port and an exhaust port disposed on opposite sides of the driving end of the piston, and movement of the driving end of the piston away from the diaphragm between first and second predetermined positions simultaneously closes the exhaust port in the cylinder to thereby permit pressure buildup proximate to the driving end of the piston and opens a bypass passageway permitting the compressed gas from the inlet port to contribute to the pressure buildup.
Furthermore, in the all-purpose signaling device mentioned immediately above, the selector switch assembly includes a selector cup with at least two attached leg members adaptable for joint rotation with the cup, wherein only one of the legs is positioned adjacent a flow inlet of one of the first and second signaling components when the cup is in a first predetermined position and wherein only the other of the legs is positioned adjacent a flow inlet of the other of the first and second signaling components when the cup is in a second predetermined position. If desired, a separate curved member can be mounted on each leg for selectively blocking one of the flow inlets when positioned adjacent thereto.
According to a further aspect, the present invention provides a pneumatic signaling device operable by compressed gas including a continuous signaling device operable at a first flowrate of the compressed gas, a percussion signaling including a single moving element and operable at a second flowrate of the compressed gas greater than the first flowrate, and a control device including a moveable member which permits operation of a selected one of the continuous signaling device and the percussion signaling device. Preferably, movement of the moveable member between first and second positions selects between the first and second flowrates required to operate the continuous and the percussion signaling devices, respectively, while positioning the moveable member to a third position establishes the selected one of the first and second flowrates. If desired, the continuous signaling component can be a gas driven horn. Preferably, the single moving element comprises a bi-stable piston. In an exemplary case, the bi-stable piston is disposed in a cylinder providing air passageways permitting undamped operation of the bi-stable piston. Advantageously, the moveable member is rotatable between the first and second positions while the moveable member permits movement to the third position irrespective of whether the moveable member starts from the first position or the second position.